Scientists conducted race-based experiments on San Jose Island where they monitored how mustard gas affected the skin of blacks, Puerto Ricans, Japanese and Caucasians

The U.S. has agreed to destroy chemical bombs left over from a secret U.S.-Canadian test program that conducted mustard-gas experiments on various ethnic groups during the Second World War.

The eight bombs were discovered on San Jose Island, the site of an extensive wartime chemical weapons test program and, later, the location for several seasons of the Survivor reality TV series.

The weapons on the Panamanian island will be destroyed in September.

Canada’s Department of National Defence had warned years ago that Canadian-made mustard gas and other chemical weapons might still be found on the island, according to documents obtained by the Ottawa Citizen through the Access to Information law.

The failure by the U.S. and Canadian governments to commit to cleaning up the contaminated island has angered Panamanian officials for years. The chemical bombs were discovered in 2002 but it has taken until now to get the U.S. to agree to dispose of the weapons.

More than 30,000 chemical bombs were detonated on the island during the U.S.-led program. One report indicated that there could be up to 3,000 bombs still intact and scattered in the jungles on San Jose.

Canadian DND scientists also noted in one report that in 1974 a worker at a construction site on the island suffered burns from a mysterious substance.

Still, a Panamanian company developed a small resort on a portion of the island. San Jose was temporarily closed down in 2001 after chemical weapons were found but it was reopened so the Survivor reality TV series could film segments on the location’s white sandy beaches several years later.

Canada is not participating in the disposal of the bombs, a Global Affairs Canada official said Monday.

But in the past, Canadian diplomats have tried to either deny Canada’s involvement in the Second World War testing or have claimed that Canada never left any weapons behind.

Canada supplied much of the mustard gas used in the U.S.-led test program as well as 1,000 bombs, DND records show. Canadian chemical warfare specialists from Suffield, Alta., helped design some of the tests and Canadian pilots took part in the bombing raids.

Susan L. Smith, a University of Alberta historian, said Canada was a significant participant in the chemical weapons testing on San Jose Island. “This was an area where Canada indeed punched above its own weight,” said Smith, author of a new book called Toxic Exposures, which chronicles mustard-gas use during the Second World War.

During her research, Smith found that scientists conducted race-based chemical warfare experiments on San Jose Island. Scientists monitored how mustard gas affected the skin of Puerto Ricans and Caucasians, during the tests. Other tests in the U.S. focused on blacks and Japanese. Smith noted that all individuals, no matter what their ethnicity, suffered extensively from the mustard-gas exposure.

At one point, the U.S. considered using mustard gas as a method to kill Japanese troops hiding in bunkers and other fortresses on Pacific islands. Tests on San Jose Island were key in those preparations but the Americans decided not to proceed with using the weapons.

It will take between six and eight weeks to dispose of the eight weapons, Panamanian officials have said.

“Canada has a moral commitment to help clean up the mess it created,” Smith added.

A DND report noted that Canadian-made mustard gas may still be on the island since the heavy metal shipping containers they were transported in were robust and would have survived over the decades. Some bombs that did not detonate would also still contain mustard gas or other chemicals.

In other cases, the mustard gas would have dissipated but it would have produced toxic byproducts in the soil. Lewisite, another chemical tested on San Jose, decomposes into arsenic, Smith noted.

Panama, which has few resources to deal with chemical weapons, had asked Canada in 2001 to help it conduct a comprehensive search of San Jose Island for abandoned bombs. Canada, however, refused.

That didn’t, however, stop Canadian diplomats in the same year from asking Panama to financially support Canada’s efforts to rid the world of land mines.

The Panamanians pointed out that they didn’t have any minefields in their country but did have thousands of abandoned U.S. and Canadian bombs.

The Canadian diplomats backed off their request, pointing out that the situation could get embarrassing for Canada. “At present we see considerable risk of a public affairs failure if we were to proceed,” the message to Ottawa at the time noted.